A free feast made from six tonnes of misshapen fruit and veg that would otherwise have been thrown out will be offered to up to 5,000 people in Trafalgar Square.

Curry and smoothies will be served at Feeding The 5,000 on Wednesday from noon to 2pm, to highlight food waste.

Farms, packers and markets have given fruit and veg to the event, organised by author Tristram Stuart with Save the Children, ActionAid, This is Rubbish and FareShare. Chefs, including Masterchef winner Thomasina Miers, will give lessons in using leftovers.

Rosie Boycott, chairwoman of the London Food Board, said: "It will bring to life the idea that every morsel is too good to waste." Britain wastes £12billion of food and drink a year. Up to 40 per cent of farmers' crops are rejected for cosmetic reasons.